C2956 Diagnostic Trouble Code

C2956 is a kind of OBD-II Diagnostic C-Chassis Diagnostic Trouble Code.

It is considered generic because it applies to all makes and models of vehicles, although specific repair steps may be different depending on your car model.

Symptoms

Symptoms of a C2956 diagnostic trouble code may include:

Diminished fuel efficiency
Fuel pressure too high
Malfunction Indicator Lamp (MIL) illuminated
Misfire

Possible Causes :

Faulty IMRC actuator/sensor
A large vacuum leak would cause a massive amount of un-metered air to enter the intake manifold resulting in an overly lean mixture.
Low fuel pressure caused by a clogged filter, failing fuel pump, failed fuel pressure regulator or clogged or leaking injectors.

Repair Processes :

Pack the connector cavity with dielectric silicone compound (same stuff they use for light bulb sockets and spark plug wires) and reassemble. Find out what kind of system you have and verify that voltage to the fuel level sensor is present at the fuel pump wiring harness.

Process Tips

Diagnostic trouble code C2956 is not difficult to diagnose and repair. Thus, it always pays to have a qualified technician to look after your vehicle should this error code arise.

Diagnosing this code requires the engine to be in good running shape, without unmetered air entering the engine. If other codes that relates to misfiring condition, lean running or air entering the engine is present, then you must first fix those error codes before C2956.

Fortunately, C2956 is a fairly common OBD code, meaning that it applies to all makes and models of vehicles made after 1996.

C2956 Trouble Code For Specific Cars

C2956 Daimler Majestic Heated Backlite Input Circuit Short To Ground
C2956 Volvo 264 SCP (J1850) Invalid or Missing Data for Door Locks
C2956 Mercedes-benz Bionic Air Conditioner Refrigerant Charge Loss
C2956 Subaru Forester 3 Left Lamp Outage Signal Circuit Short to Ground
C2956 Rover 400 Ignition Coil A Secondary Circuit Malfunction
C2956 Mazda Mx-flexa 1-4 Upshift (Skip Shift) Solenoid Control Circuit Malfunction
C2956 Smart Brabus Lamp ABS Warning Output Circuit Failure